Spread your wings and fly away!Follow article
Fifteen years ago, Joerg Weinmann was invited to a 737 flight simulation session at Frankfurt airport. This experience was so impressive that he joined the flight simulation internet community and started to build his high-quality components for a flight simulator. He started his business “simparts” and soon became one of the major online component sources for the community. Today “simsystems” components are used for professional flight simulators all over the world, not only for entertainment but also for research and education.
Vdh: I know that you have a US flight license, so you are familiar with flight instruments. But what is your professional background for producing highly sophisticated electro-mechanical replicas?
Joerg: Before I started my business, I was an executive producer at SDR (a German broadcasting company).
Vdh: Producing broadcasts seems to be far away from producing electro-mechanical parts.
Joerg: Well, the point is that both are computer-based today. Our production line is fully digital. We construct everything in 3D CAD and then let the machines do the rest. So you do not need to be a trained mechanic to operate a CNC router.
Vdh: Why is it necessary to reconstruct the parts for a simulator? Couldn’t you use the original equipment?
Joerg: That’s all a matter of costs. Original aviation parts must be certificated and are very expensive. As a rule of thumb, you can add two zeros to the price of a regular part like a rocker witch. Buy one at RS for 5.3 €, and you will have to pay 530 € for an original certificated aviation switch of the same size. A complete auto-pilot panel for the Boeing 737 costs about 350,000 $ while our replica “only” costs 65,000 $. That’s different for automotive simulation, and therefore you will often find original parts in car simulators.
Boeing 737 simulator's cockpit with simbus CAN driven panels, manufactured by simsystems
Vdh: Who are your customers?
Joerg: There are three main groups: The engaged private hobbyist with high-quality demands, the professional entertainment sector (at airports, museums, fun parks) who sometimes hire their systems for vocational preparation of pilots, and then we have the educational and research sector (see this video for a 747 educational simulator):
Training centres for flight engineers and modules for professional flight simulators used by military and pilot training. If real helicopters get a new version of a panel, all the simulators must get the same changes. We do not build the complete professional simulators with all their safety and hydraulic systems to move the cabin. Those 15 to 25 million dollar simulators are more the business of the “big players”. But we deliver the cockpit or just the cockpit components for some of them, like CAE. This has become an international business for us with partners all over the world in Asia, America and Europe. One of our customers is a US military supplier delivering the Eurocopter simulators wit parts from simsystems.
Vdh: The private customers from the simulation community have been your first clients. Are you still producing parts for them? Tell us a bit more about those hobbyists investing a fortune for their private simulator.
Joerg: Yes, we still run simparts as an online shop. But today, the significant business is with professional clients. You will find all kind of people in the hobbyist’s scene. One of our clients is a Jumbo Jet pilot who wanted his personal jet in the basement of his house. Most of them build their systems over many years, just like in the model railway scene. They often spend the value of a sports car to realise their dreams. But you need to know that our components for the hobbyist’s scene are the same high-quality products as those we use for professional simulators. Most of the private users try to save money by investing their time to assemble the small parts instead of buying a complete panel.
Artificial horizon replica from simparts
Vdh: What makes quality in your business?
Joerg: A licensed part for a professional simulator must look, feel and behave like the original part. If a simple original push-button, e.g. has a 15 Newton switch point, the replica must have a similar working point. The torque for a replica rotary switch must be equal to the original. The colour and brightness of a signal must be equal to the original.
Vdh: So you must know all the original values. Isn’t this the most challenging task of your business?
Eurocopter EC135 instrument control panel, manufactured by simsystems
Joerg: Sometimes we get data and plans of the original panels but most of the time we need to get the original part, measure and reconstruct. Sometimes we use 3D scanning to achieve the same look. But replica is not a copy of the original. In a simulator, you don’t have the feedback forces of hydraulic systems. We need to simulate such forces by using servo motors and precise torque control. The last three years, we have developed a CAN bus controlled “load control system” to simulate original forces and torques. That’s the challenge: We need to find the most reliable and yet affordable way to get the same look, feel and behaviour.
Wire driven mechanical load to simulate steering torque, controlled via simbus CAN.
Vdh: For me, a cockpit is a wall of dials and instruments. How many signal lamps and switches are in a modern aeroplane? Do they still have this old school mechanic dials and with things like a vertical gyro (“artificial horizon”) aren’t they very complicated to be imitated with motorised movements?
Boeing 747 simulator's cockpit with simbus CAN driven panels, manufactured by simsystems
Joerg: We have estimated the complete number of signal lamps in a Boeing 737 to be about 210. Ant the number of switches is about 300 (each warning lamp is always also a switch to check the functionality of this signal). Modern cockpits no longer have mechanical dials, so that is something just for historical planes like our replica cockpit of a Me 109 with only mechanical dial instruments. (watch on this video how the handcrafted gauges are assembled).
But yes, these dials are a great challenge and clockmaker work. We use parts from traditional clockmaking suppliers and small steppers to construct the replicas. So a replica is often much more complicated than the original gyro. A modern cockpit has lots of screen panels instead. One of the latest private turboprop planes, the “Pilatus PC-12 NGX” replaces most buttons and lamps with touch screens. These modern instruments are mostly made by Garmin, the GPS navigation expert company.
Eurocopter EC135 simbus CAN driven instrument, manufactured by simsystems
Vdh: You always talk about “panels”. Could you please explain this concept a little bit more?
Joerg: In aviation, they have developed a very modular design concept. You have units of instruments which are easily replaceable, called “LRU” (for “line replaceable unit”). Traditionally these LRUs have connectors with many contacts, and if they fail, they can be replaced in minutes during a ground stay to get the plane back into the air. Today, some LRUs work with digital bus systems. But traditionally every switch and lamp has its dedicated wire and contact. Often you even have redundant wires for safety reasons. So in such a cockpit, you will find several kilometres of wires. The LRUs work with very uncommon voltages: 28 V or 115 V at 400 Hz and 5 V 400 Hz for the background lights. Our replica panels work with 24 V 50 Hz and 5 V for the lights.
Eurocopter EC135 simbus CAN driven Line Replaceable Units, manufactured by simsystems
Vdh: I would like to see more such modular concepts in cars and also the automation industry. It would make things much better testable, and we would have much better up-times. But let’s talk about the control systems. What kind of computers and software is used to control the complete simulators?
Joerg: You normally have several computers controlling the simulators. Each one has its dedicated task: Main server, safety system, visual projection system, motion system, aerodynamic flight model calculations, indicators and controls, and so on. Every multifunctional display panel has its associated computer. They all work together in real-time. We often need to adapt our controllers to get them integrated into such a complex system as there are no normed protocols. In professional systems, they mostly use Linux based computer and controller. The software is also split. For fixed base entertainment simulators, we use the software from ProSim-AR, which is doing the main simulation task. Many of our panels are intelligent subsystems which have their built-in controller and software.
Vdh: And you designed your propriety CAN based bus system “simbus” to connect your panels to the controller, right?
Joerg: Yes. In the hobbyist’s scene USB based IO boards have been used for ages. But once you have a dozen USB controller boards in your Windows PC, you know what this “dingdong – dongding” sound means: Due to power overload or connectors problems your USB connections tend to fail, and this ruins a simulated flight. In professional simulators, 40 years ago, they used classical industrial PLCs to connect outputs and inputs with kilometres of wires. So I started evaluating this concept and used the reliable CAN concept, which was already successful in automation for many years. By that time they had already used the “CAN aerospace” protocol in aviation panels. So we used this protocol to build on. We developed mixed in- and output boards communicating with this protocol. Using these boards in our panels, we could reduce the wiring to just five cores and a single plug: CAN+/-, 24V, GND and shield.
Vdh: And you published your drivers and software on Github. Why are you sharing your IP?
Joerg: Making it public broadens the potential market for our products. The customer gets our IO board and can use his firmware on his CAN gateway or controller. When we have shown our system to people not involved in flight simulation, they have already several ideas in mind how to use our simbus for their purpose. One of them, for example, started using the system in his mobile home. In my eyes, the wiring of luxury yachts could perfectly be done with simbus. I would love to enhance the custom software development by introducing a modern “block wiring” software like Node-RED for our modules.
Vdh: Would you work together with a community to develop such a software tool?
Joerg: Of course! I would appreciate it very much if we would get contributions to offer such a tool. Business networking is essential for a small company like us: Together, we can achieve much more!
Vdh: You are not only involved in large scale projects and the essential after-sales service. You are also offering customer-specific production of low volume CNC parts. You have, e.g. made some parts for my useless machine 3 (UM3).
Joerg: Yes, we try to optimise the degree of capacity utilisation of our expensive machines by offering such services. But we are specialised on simulation, that’s our expertise. So if someone needs to get a functional replica of a real world’s part, we can do that. We have simulated folk lifters and many other machines.
Vdh: What is your vision for the future?
Joerg: I would love to see our products and services being used for applications which really make a change in this world. For example, in hydrogen technology for the energy market. I would not even care about the return of investments. When talking about green energy and saving our planet, we get the best return of investment for the next generation.
Vdh: This is a beautiful vision and a perfect attitude. Thanks so much for the interview and all the best for your future!